A fortnight ago, I looked at the Quercy side of south-west France. This week it's the turn of Gascony, stretching west from Toulouse to the Atlantic and the Pyrenees. Gascony is home to the dark, tannat-based reds of Madiran, Saint Mont and, nestling in the Pyrenean foothills, the independent-minded Basque sub-region of Irouléguy. So goodbye for now to the malbec of Cahors and hello fer servadou – known as pinenc in Saint Mont – and the dark reds made from tannat grape, the variety found by Dr Roger Corder to be the richest in the anti-oxidant chemical procyanadin.

The best whites of the region are made from the gros manseng and petit manseng grape, to be found in Jurançon and the Côtes de Gascogne. Gros manseng makes fragrant and crisply fruity dry whites, and when blended with the local courbu and arrufiac, as in the case of the 2008 Saint Mont, £6.99, Marks & Spencer, it can be crisp and refreshingly dry. A south-western French answer to New Zealand sauvignon blanc, fine gros manseng like the 2008 Domaine des Cassagnoles Gros Manseng, Vin de Pays des Côtes de Gascogne, £6.90, Free Run Juice (freerunjuice.co.uk), The Wine Shed, Somerset (01984 624641), can be beautifully aromatic with a zesty grapefruity character. In company with the smaller, thicker-skinned petit manseng grape in Jurançon, it can make wines of the class of the delectably bone-dry 2005 Clos Lapeyre Vitatge Vielh Jurançon Sec, £13.75, Les Caves de Pyrène, Guildford (01483 554750).

Madiran, Claes Lofgren

Madiran today is one of the south-west's most dynamic regions – thanks in part to the development here by Patrick Ducourneau of a frightening-sounding method of taming the tough tannins of the tannat known as micro-oxygenation. His discovery that bubbling oxygen through the fermenting juice helps to soften an otherwise potentially tough variety is now used to produce a more immediately fruity style here, and worldwide. In Saint Mont the Plaimont Co-op adds a touch of cabernet sauvignon and pinenc to bring a certain sweet blackcurrant character to dark-fruited, chocolatey blends such as the 2005 Monastère de Saint Mont, £13.99, Bedales, London (020-7403 8853).

The special climatic conditions, proximity to the Atlantic and the Pyrenees give Madiran's reds, with both cabernets and fer also used, their robust, tannic and long-lived quality. A classic Madiran, the 2007 Chateau d'Arricau-Bordes, Cave de Crouseilles, £14.99, The General Wine Company, Hants (01428 722201), a blend of tannat, cabernet sauvignon and cabernet franc, shows coffee-bean spicy oak and vibrant brambly fruit underscored by spiciness. Excellent too, the 2006 Château Aydie, Vignobles Laplace, £11.99, Waitrose, displays pure ripe dark cherry and mulberry fruit, framed by spicy oak and damsony acidity in the modern style – a perfect example of the taming of the tannat.

Madiran, Wine Society

Irouléguy, lying in the heart of French Basque Country in the Pyrénées-Atlantiques, is comparatively small, with only 215 hectares of vineyards planted on spectacularly steep, sunny, south-facing terraced vineyards. Typically using half tannat and half cabernet franc and cabernet sauvignon for freshness and fragrance, the 2007 Domaine Arretxea, Irouléguy, £14.99, Les Caves de Pyrène, Zelas (zelas.co.uk), is an attractive Basque blend, vivid and fresh and with no oak, a distinctive contrast to, well, just about anything you've ever come across.

Something For the Weekend

Under a Fiver

ASDA Extra Special Merlot, Domaines Paul Mas, Vin de Pays d’Oc

Pure southern French merlot, this barbecue-friendly red from Jean-Claude Mas shows bright cherryish fruit and a hint of capsicum, subtly rounded out with partial ageing in oak. £4.86, down from £6.07, today only.

Under a Tenner

2008 D’Arenberg the Hermit Crab Viognier Marsanne

From McLaren Vale’s eccentric Chester Osborn, this Aussie take on two of the best white Rhône varieties is heavily scented with dried apricots and rich in opulent, almost off-dry, peachy flavours. £6.74, until 30 June, normally £8.99, Waitrose.

Splash Out

2007 Schug Carneros Chardonnay

This California white hadn’t clicked with me until this vintage, but all of a sudden the balance is just so, a beautifully upholstered burgundian-style chardonnay with a richness of flavour, fine acidity and a nutty oak veneer. £16, Marks & Spencer.